Having done that you will now see that when you open the python window you will now have the following 2 options:

SubMenu
SubMenu 1

Those SubMenus will allow you to add more python scripts.  So when you want to add a script, you edit the SubMenu.py or the SubMenu1.py  file  instead of the MainButtons.py file.

"It is good to see ourselves as others see us. Try as we may, we are never
able to know ourselves fully as we are, especially the evil side of us.
This we can do only if we are not angry with our critics but will take in good
heart whatever they might have to say." - Ghandi